Vitamin C (ascorbic acid)

Based on secondary sources, vitamin C deficiency may cause fatigue, personality changes, and a decline in psychomotor performance. Long-term vitamin C deficiency results in symptomatic scurvy, which is characterized by gingival swelling and bleeding; loosening of the teeth; hyperkeratosis; perifollicular hemorrhages; petechial hemorrhages in the viscera; and hemorrhages into the muscles of the arms, legs, and joints (131; 132; 133; 134). Severe scurvy may progress to neuritis, jaundice, fever, dyspnea, and death. In infants, vitamin C deficiency is initially manifested as listlessness, anorexia, irritability, and failure to thrive. Later symptoms result from hemorrhage and collagen deficiency, with seizures, shock, and death if left untreated.

AntibioticsAntibiotics: In a systematic review, the effects of vitamin C were decreased by tetracycline antibiotics such as doxycycline (Vibramycin®), minocycline (Minocin®), or tetracycline (Sumycin®) (25).

TobaccoTobacco: In children and adolescents exposed to environmental tobacco smoke, serum ascorbic acid levels were linearly related to serum cotinine levels (r=0.19) and, after controlling for confounders, environmental tobacco exposure remained significantly associated with lower levels of serum ascorbic acid in children who were exposed to both high and low levels of ETS (96; 97). The relationship of plasma and dietary vitamins C and E and tobacco use in adults has also been examined (98). Additional details are pending.

Vitamin B12Vitamin B12: Large doses of vitamin C may interfere with the absorption and metabolism of vitamin B12, according to secondary sources.

The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.